Multiple mode fluid amplifier



2, 1969 w. M. SOWERS 3,460,556

MULTIPLE MODE FLUID AMPLIFIER Filed Feb. 28, 1966 2 Sheets-Sheet}.

INVENTOR WALKER MORGAN SOWERS A TORNEY- Aug. 12, 1969 W. M. SOWERS MULTIPLE MODE FLUID AMPLIFIER 2 Sheets-Sheet 2 Filed Feb. 28. 1966 RESET FLOW MIL/EN ran WALKER MORGAN SOWERS FROM SOURCE ATTORNEY FIG. 7.

United States Patent 3,460,556 MULTIPLE MODE FLUID AMiLIFIER Walker Morgan Sowers, Merrimack, NH, assignor to Sanders Associates, Inc., Nashua, N.H., a corporation of Delaware Filed Feb. 28, 1966, Ser. No. 530,686 Int. Cl. F15c 1/10 US. Cl. 137-815 Claims ABSTRACT OF THE DISCLOSURE A fluid amplifier having several stable states, among which it can be switched in any order or sequence. The device illustrated and described includes a main fluid stream and eight outlet ports to any one of which it may be switched by operation of the appropriate one of eight control jets.

This invention relates to multi-stable fluid amplifiers and more particularly to a fluid amplifier capable of switching to any of a multitude of stable positions.

The fundamental characteristic of the fluid amplifier is that it is capable of a bi-stable mode of operation. For example, the main fluid stream in the fluid amplifier may be deflected by a control jet into one of two output channels and by virtue of the wall etiect will remain in the channel it is directed to even after the termination of the control jet. All channels in such amplifiers are usually constructed in a single plane and are formed by a sandwich of plates one of which contains the pattern of channels. Therefore, such amplifiers are two dimensional devices and in operation are analogous to the electronic bi-stable flip flop circuit. Bi-stable operation only is permitted because in the two dimensional arrangement only two walls are available against which the main fluid stream adheres in accordance with the wall eflect and it is this wall effect which makes the device stable in two positions.

It is an object of the present invention to provide a fluid amplifier which is stable in more than two positions.

It is another object of the present invention to provide a three dimensional fluid amplifier having a multitude of stable states.

It is another object of the present invention to provide a three dimensional fluid amplifier having a multitude of stable states and which is capable of switching between said stable states in all possible sequences.

It is another object of the present invention to provide a counter operating in accordance with principles of the fluid amplifier.

The present invention provides a fluid amplifier capable of assuming more than two stable states. Embodiments of the present invention include a main fluid stream which is injected into an interaction chamber which feeds a channel that diverges in three dimensions. A multitude of control jet orifices encircle the point of injection and serve to direct jets of control fluid against the main stream causing it to deflect to any of a multitude of different positions arranged along said diverging channel. At each diflerent position, the main stream adheres to the divergent channel wall by virtue of the wall effect and so the main stream remains in the position until the control streams deflect it to another. At the end of the divergent channel are a multitude of outlet ports each positioned to receive the main stream when positioned at a different one of the stable positions along the divergent channel wall.

In one embodiment of the invention, the divergent channel is an annular passage extending from the inter action region to a multitude of output ports arranged in a circle. The outer wall of the annular passage is preferably grooved or fluted to define shallow channels each aligned with a different one of the output ports and leading directly thereto. In another embodiment, the output ports are arranged in an array of two rows at the end of the diverging channel, the inner walls of which define a generally rectangular shape in cross section and are preferably grooved or fluted, each groove leading to a different output port. A variation of this latter embodiment is useful as a binary counter.

Other objects and features of the invention will be apparent from the following specific description taken in conjunction with the figures in which:

FIGURE 1 is a sectional side view of an embodiment for switching the main stream among ports arranged in a ring with no limitation as to switching sequence;

FIGURE 2 is an end view of the device illustrated in FIGURE 1;

FIGURES 3 and 4 are sectional views of the device in FIGURES 1 and 2;

FIGURES 5 and 6 are sectional views of an embodiment including an array of output ports arranged in rows and columns and in which the main fluid stream is positioned about the array by control jets directed against it;

FIGURE 7 is a fluid schematic showing use of the device in FIGURES 5 and 6 to provide a binary counter;

FIGURE 8 is a diagram illustrating the wall effect as an aid to understanding the operation of the invention; and

FIGURE 9 illustrates vector forces in operation in the device shown in FIGURES l to 4.

FIGURES 1, 2 and 3 illustrate an embodiment of the invention most useful as a sequential switch operating analogous to a rotary electrical switch but having greater versatility. The sectional view in FIGURE 1 illustrates an inlet channel 1 for the main flow 2; which may be a gas or liquid obtained from a source at suitable pressure and delivered to the inlet channel. The main fluid stream 2 is injected from a converging portion 3 of the inlet into the interaction space 4 wherein control jets 5a to 5h issuing from orifices 6a to 6h impinge upon the main stream and compel the main stream to flow along the diverging inside wall portion 7 of the diverging channel 8 in one of the shallow channels 9a to 9h defined along the inside of the diverging wall as illustrated in the sectional views of FIGURES 3 and 4.

Each of the channels 9a to 9h lead to an outlet port correspondingly lettered 10a to 10h. These outlet ports consist of tubes mounted in a plate 11 which is equipped with holes for accommodating the tubes in registry with the correspondingly lettered shallow channel. The diverging channel 8 seals to the plate 11 and the outlet ports are sealed to the plate so that the shallow channels 9a to 9h lead directly to the outlet ports 10a to 10h and suitable conduits or tubes connect the ports to utilizing equipment.

The control fluid which issues from the orifices 6a to 611 and causes the main stream 2 to flow along one or the other of the shallow channels, may be derived from the same source as the main stream of fluid or the control fluid may be derived from another source. In either event, the flow rate of the control fluid even while initiating control action upon the main fluid stream is substantially less than the flow rate of fluid in the main fluid stream as is typical of fluid amplifiers. The eflect of the control jets on the main fluid stream is demonstrated diagrammatically in FIGURES 8 and 9. FIGURE 8 demonstrates the wall effect on the main stream. As shown in FIGURE 8, the main stream 2 is injected into the interaction space 4 wherein a control jet 5e impinges upon the main stream 2 and deflects it against the wall 7. The main stream must be deflected an angle 0 in order to he placed against the wall 7. The deflection angle is dependent upon the ratio of momentums of the control jet e and the main stream 2. From conservation of momentum it can be seen that (i=tan- M /M where M is the momentum of the control jet and M is the momentum of the main fluid stream.

The wall effect contributes to maintain the main fluid stream 2 in the channel 9a after the control jet 5e has been turned off. The wall effect stems from the phenomena that a fluid stream such as the main stream 2, flowing in close proximity parallel to a wall such as channel 9a, tends to attach itself to the wall. The reason for this is that as the stream moves it entrains more fluid from the surrounding medium and this entrained fluid must be made up from fluid from afar. Since the wall is close to one side of the stream, the flow of replacement fluid to this side of the stream is impeded and results in a slightly lower pressure on the side of the stream closest to the wall. As a consequence, a slightly greater pressure on the opposite side of the stream forces the stream to cling to the wall making it even more difficult for replacement fluid, represented by arrows 12, to flow into a low pressure pocket region 13 created just upstream of the point of attachment of the stream to the wall. Thus, as shown in FIGURE 8 the main fluid stream 2 attaches to the wall and remains attached to the wall until the momentum of a control jet issuing from the adjacent control orifice 6a is sufficiently great to cause the main stream to deflect away from the Wall.

A conical center body 15 pointing upstream is posi tioned in the diverging channel 8 and spaced concentric therewith so as to define a diverging annular passage therewith. The center body 15 aids to channel the main stream to the selected output port and is not entirely necessary for operation of the device. The center body could be dispensed with and a centrally located output port 16 in the plate 11 could be added as shown by the phantom lines in FIGURE 2, to carry off the main stream when it is not deflected to any of the output ports a to 10h. The center body does not limit the number of different sequences of switching that are possible with the device and which give the device a degree of versatility greater than the analogous rotary electrical switch. For example, flow can be switched from output port 10a to We or between any other of the ports in any desired sequence. Furthermore, there are numerous possible methods for directing control fluid jets against the main fluid stream to accomplish the switching sequence.

In operation, the main fluid stream may be switched between two oppositely located output ports such as 1001 and 10e by turning on the correspondingly lettered control jet. For example, the main fluid stream can be switched from port 10a to 10e by turning on control jet 5a which is launched against the main fluid stream from orifice 6a. Conversely, the main fluid stream can be switched from port 10e to 10a by turning on control jet 5e which is launched from orifice 6e against the main stream. Other combinations of control jets can be employed to switch the main stream to a given output port. For example, the main stream 2 can be switched from port 10e by turning on all of the control jets except jet 52. The combined momentum of all of the jets except 5e will add to the momentum of the main stream to produce a resultant directed toward port 10s. This unbalance of control jet momentum is illustrated by the vector diagram in FIGURE 9. The jets 5b, 0 and d and jets 5 g and h which appear to cancel each other will tend to move the main stream directly to the port Me in the plane defined by the axis of port 10a and the axis 17 of the device and so any tendency of the main stream to move out of this plane will be corrected by these control jets. The same effect could be achieved by turning on jets 5a, 50 and 5g or jets 5a, 5b and 5h. Generally, this technique for switching from one outlet port to another causes the main fluid stream 2 to move toward the axis 17 and across the point of the center cone 15 on the way to the new position and this is the case whether switching is between oppositely disposed outlet ports or between adjacent outlet ports. Consequently, the switching can be accomplished in any desired sequence and is not limited to the clockwise or counterclockwise rotary sequence of the analogous rotary electrical switch.

FIGURES 5 and 6 are sectional views taken through a multi-port fluid switching device formed in a block 20 of suitable material. The device includes two columns 21 and 22 and four rows 23 to 26 of ports with separate sets of control orifices formed in the block fed from control fluid ports such as 18, for producing row and column control jets which impinge upon the main stream of fluid 27 fed to port 19. The main stream is launched into the interaction space 28 from channel 29 wherein the control jets impinge upon it and direct it to one of the output ports. In the interaction space 28, the row control jets 31 and 32 issuing from orifices 33 and 34, shown in FIGURE 6, tend to direct the main fluid stream into a port in one of the rows and the column control jets which issue from orifices 37a to 37d and orifices 38a to 38d tend to direct the main fluid stream into a port in one of the columns. In this embodiment, the row control jets 31 and 32 strike the main stream 27 at a point upstream of where the column control jets strike the main stream. This is preferred when the device is used as a multistable switch. On the other hand, for some applications it may be preferred that one or both of the row control jets strike the main stream downstream of the point where the column control jets strike or, it may be preferred that all control jets strike at the same point.

In operation, one of the column control jets from orifices 37a to 37d on one side of the main stream 27 or one from the orifice 38a to 38d on the opposite side of the main stream, impinges upon the main stream and directs it to the correspondingly lettered oppositely disposed channel 41a to 41d or 42a to 42d which lead to the ports 43a to 43d or ports 44a to 44d, respectively. For example, the jet from orifice 38a directs the main stream to channel 41a which leads to port 43a. The row control jets 31 and 32 position the main stream 27 between each pair of opposed column control jet orifices and so the main stream can be directed to any one of the outlet ports in any sequence desired and when all control jets are turned off, the main stream will continue to flow out of the selected port by virtue of the wall effect.

In some applications, depending on the dimensions, type of fluid and fluid pressure, it may be necessary to maintain the row control jets 31 and 32 on in order to keep the main stream 27 positioned in the selected row. The partial walls such as 39 and 40 between the adjacent channels 41a to 41d and 42a to 42d, respectively, define the diverging channels and afford sufficient wall area in each of the channels for the main stream 27 to cling to. Thus, in preferred embodiments, the wall effect is suflicient to maintain the main stream in the selected channel even though all control jets including the row control jets 31 and 32 are turned off.

The switching device shown in FIGURES 5 and 6 can be employed in conjunction with a fluid flip flop device to provide a binary counter for counting fluid flow pulses.

When used in this manner, it is preferred to close row control orifice 33 and instead use another row control orifice 47 on the same side of the interaction space which produces control jet 48 that impinges upon the main fluid stream 27 downstream of the point of impingement of the control jets from the column control orifices 37a to 37d and 38a to 38a. The reason for this will be apparent from the following description of the counte hown in schematic form in FIGURE 7.

FIGURE 7 illustrates use of the switching device 49 constructed as described above with reference to FIG- URES 5 and 6, in conjunction with a binary flip flop structure 50 to provide a binary counter.

The binary flip flop structure 50 functions analogous to a single input bi-stable multivibrator. That is to say, it has two stable conditions of operations and switches between them each time a pressure pulse is produced in fluid control channel 51 applied thereto from a source 52 so that the flip flop delivers a steady flow of fluid to the odd manifold channel 53 or the even manifold channel 54 depending upon whether an odd number or even number of pulses have occured in the control channel 51.

The fluid flip flop 50 is made up of interconnecting NOR elements 55a and 55b. The NOR elements include main flow input channels 57a and 57b which conduct a main flow of fluid to interaction spaces 58a and 58b, respectively, from which the main flow takes one of two paths. When no control jets are applied to the interaction spaces of these NOR devices, the main flow in each flows from the interaction space out of the ZERO state channels 60a and 59b. When on the other hand, control jets are applied to the interaction regions, the main flow flows out of the ONE state channels 59a and 60b. Assume, for example, that NOR element a is in the ZERO state; that is, the main fluid stream for this element is flowing out of channel 604:. A portion of this flow in channel 60a is conducted via channel 61a and delivered as a control jet at the interaction space 58b of the b NOR element causing the main fluid stream of the b element to flow out of channel 6012. Thereafter, when a flow pulse of suflicient magnitude is produced in the input channel 51, the main fluid stream in the a NOR element will switch to channel 59a and the main fluid stream in the b element will switch to channel 59b, because there will no longer be any control jet delivered via channel 61a for maintaining the b stream in channel 60b. The main flow of element a will remain in channel 59a by virtue of a control jet delivered to this element via channel 61b which taps off part of the flow from channel 59b and so the flip flop 50 assumes a stable condition with the main fluid stream flowing out of manifold channel 53.

Upon the arrival of the next pulse from input channel 51 the main fluid stream of NOR element a switches to channel 60a and the main fluid stream from NOR element b switches to channel 60b. Thus, the main flow is in manifold channel 53 following odd numbered pulses and in manifold channel 54 following even numbered pulses.

The manifolds 53 and 54 conduct fluid to the control orifices 37a to 37d and 38a to 38b, respectively on op posite sides of the interaction space 28 of switch 49 which is constructed substantially as described above with reference to FIGURES 5 and 6, but employs row control orifice 47 producing jet 48 rather than orifice 33. Simultaneously, fluid is fed from manifold 53 into all of the column control orifices 37a to 37d on one side of the interaction space. Similarly, manifold 54 conducts fluid simultaneously to all of the column control orifices 38a to 38a on the opposite side of the interaction space.

In the switch 49, the row control orifice 34 provides a control jet against the main fluid stream 27 which resets the main stream between orifices 37a and 38a and holds the main fluid stream there until the control jet from one of these drives the main stream into the opposite diverging channel 41a or 42:: so that the main flow 27 is out of port 43a or 44a. When flow is out of port 44a the count of one is indicated and when out of port 43a the count of two is indicated.

Fluid to row control orifice 47 is tapped off the odd manifold line 53 via line 62 so as to produce a control jet which strikes the main stream 27 just after the jet from orifice 37a comes on following the first pulse. Since, the main stream will be centrally located in the reset or clear position, as shown in FIGURE 7, the jet from orifice 37a which strikes it first will move it to channel 42a which feeds port 44a indicating a count of one. Thereafter, upon the arrival of the second pressure pulse in line 51, manifold 54 conducts and manifold 53 does not and so the main stream 27 is compelled by the jet issuing from orifice 38a to flow along channel 41a which feeds port 43a indicating a count of two. Following the third pulse, .the jet from orifice 37a comes on again and moves the main stream 27 once again to a central position where the jet from orifice 47 strikes it with suflicient momentum to move the main stream along a course represented by the broken line 63 to the space between orifices 37b and 38b at which point the jet from orifice 37b will take over and move the stream 27 out of line with the jet 48 from orifice 47 and into channel 42b which feeds port 4% indicating a count of three. Thereafter, upon the arrival of the next pressure pulse in line 51, manifold 54 conducts and manifold 53 does not and so the stream 27 is compelled by the jet issuing from orifice 38b to flow out: of port 43b denoting the count of four, and so the count of pulses in the line 51 continues. Upon the arrival of each consecutive pressure pulse in the line 51 the main fluid stream 27 in the switch 49 switches from the odd column of ports to the even column of ports and vice versa and upon the arrival of each odd numbered pulse, the main fluid stream switches from row to row of the output ports, thereby to accomplish a binary count of the pulses, the total count being represented by the port from which the main fluid stream issues. The numbers 1 to 8 shown beneath each of the column control orifices indicates the count number when the orifice compels the stream 27 into the oppositely disposed channel and port.

The various embodiments of the present invention described herein each include a main fluid stream which is injected into an interaction space in which it is acted upon by control fluid jets. The control fluid jets: compel the main fluid stream to move in three dimensions and assume a position against the wall of one of a multitude of channels leading from the interaction space to which the main fluid stream clings so that it flows from a selected output port.

What is claimed is: 1. A multi-stable fluid device comprising, an interaction chamber, means for directing a main stream of fluid into said chamber,

means for directing a plurality of jets of control fluid into said chamber, whereby said jets impinge upon said main stream,

means forming a plurality of different main stream flow paths leading from said chamber, and an outlet at the end of each of said flow paths, said paths being arranged in pairs such that each path in a pair diverges from the other path in the same pair in the direction of flow of said .main stream,

said paths in each pair defining separate planes which diverge from each other in the direction of said main stream flow,

said control jets being arranged in pairs each of which is associated with a ditferent pair of said main stream flow paths such that each of said pairs of control jets compels said main stream to flow along one or the other of the main stream flow paths of the associated pair of main stream flow paths,

the orientation of said flow paths and connection to said interaction chamber being such that said main stream when directed to any one of said flow paths by said impinging control jets adheres to said flow path by virtue of the wall effect.

2. A multi-stable fluid device as in claim 1 and in which,

at least one of said control jets is directed against said main stream transverse to said pairs of control jets so as to position said main stream for impingement thereon of selected of said pairs of jets.

3. A multi-stable fluid device as in claim 2 and includat least two oppositely directed control jets which impinge upon said main fluid stream in a direction transverse to said pairs of control jets,

whereby said two oppositely directed jets selectively position said main fluid stream for impingement thereon by said pairs of control jets.

0 4. A multi-stable fluid device as in claim 2 and includat least one control jet directed transverse to said pairs of control jets and positioned to impinge upon said main fluid stream downstream of the point of impingement of said pairs of control jets on said main fluid stream.

5. A fluid operated counter comprising,

odd and even channels,

means for alternately producing fluid flow in said odd and even channels,

an interaction space,

means for directing a main fluid stream into said interaction space,

a plurality of fluid paths each leading from said interaction space to a diflerent outlet,

means for directing a plurality of pairs of substantially parallel control fluid jets into said interaction space,

said pairs being positioned so that each impinges on said main fluid stream when said stream is in a differ ent position and each of said impinging control jets compels said main fluid stream to flow along a different one of said fluid paths,

means for directing at least one other control fluid jet into said interaction space in a direction transverse to said pairs of control fluid jets and positioned to impinge upon said main fluid stream downstream of the point of impingement of said pairs of jets upon said main fluid stream,

means for directing fluid from said odd channel to one of the jet directing means in each of said pairs and to said transverse jet directing means, and

means for directing the fluid in said even channel to the other jet directing means in each of said pairs,

whereby the outlet through Which said main fluid stream flows is indicative of the number of alterations of fluid flow in said odd and even channels.

References Cited UNITED STATES PATENTS 3,139,895 7/1964 Comparin 137-815 3,212,515 10/1965 Zisfein et al 137-815 3,246,863 4/1966 Posingies 137-815 XR 3,124,160 3/1964 Zilberfarb 137-815 3,144,037 8/1964 Cargill et a1. 137-815 3,148,691 9/1964 Greenblott 137-815 3,174,497 3/1965 Sowers 137-815 3,175,569 3/1965 Sowers 137-815 3,182,675 5/1965 Zilberfarb et al 137-815 3,186,422 6/1965 Boothe 137-815 3,208,462 9/1965 Fox et al 137-815 3,226,023 12/1965 Horton 137-815 XR 3,323,532 6/1967 Campagnuolo 137-815 SAMUEL SCOTT, Primary Examiner 

